In many applications, a dialog box is provided to allow the user to manipulate a value of a displayed variable. Typically, a number representative of the current value of the variable is displayed together with a bar graph proportional to the displayed number. The user moves the mouse pointer to an "up" button or a "down" button and repeatedly clicks or holds until the desired value is attained. Alternatively, the user moves the mouse pointer and clicks on the bar graph, drags the bar to a desired value or double clicks and the bar responsively moves to the mouse pointer.
In other applications, the user can vary the displayed value by mousing down within the boundaries of the control and dragging the mouse pointer horizontally across the screen, and releasing once the desired value is attained.
The prior art user interfaces are considered too slow for certain applications. If the user wishes to make large scale changes to a precise value, the user must first click on the bar graph to make a large scale change and then move the mouse pointer to click on the "up" and "down" buttons until the precise value is attained.
For click and drag interfaces, the mouse pointer can hit the edge of the screen before attaining the desired value. The user must then release the mouse button, move the mouse pointer back to the control in question and re-start the process to attain the desired precise value.